<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>

    <!-- <div class="demo">
        <span></span>
        <span></span>
    </div>
    <div class="demo">
        <p></p>
        <p></p>
    </div> -->

    <!-- <div class="wrapper">
        <div class="section"></div>
        <div class="section">
            <div class="item"></div>
            <div class="item"></div>
            <div class="item"></div>
        </div>
        <div class="section"></div>
    </div> -->

    <!-- <div class="demo"></div>
    <div class="wrapper">
        <div class="demo"></div>
        <div class="demo"></div>
    </div> -->
    

    <!--  -->

    <div class="wrapper">
        <div class="box">
            <div class="content">
                <div class="demo"></div>
            </div>
        </div>
    </div>

    <script src='./jquery.js'></script>
    <script>
        // wrap
        // 
        // $('.demo').wrap('<div></div>');


        // wrapInner
        // $('.demo').wrapInner(function (index) {
        //     return '<div class="wrapper' + index + '"></div>'
        // });


        // wrapAll
        // $('.demo').wrapAll('<div></div>');


        // unwrap
        // $('.demo').unwrap();

    </script>
</body>
</html>